ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
The effect of layer thickness on fatigue crack propagation (FCP) in microlayer composites of polycarbonate (PC) and styrene-acrylonitrile copolymer (SAN) has been studied. Variation in layer thickness was achieved by increasing the number of layers from 49 to 776 while keeping the overall sheet thickness and composition the same. It was found that the 776 layer composite had a larger number of fatigue cycles from crack initiation to fracture, a longer stable crack length and higher value of critical strain energy release rate J1C. Microscopic characterization of the damage zone and resulting fracture surface revealed a transition from SAN crazing to shear deformation as layer thickness decreased from 18 to 1 μm; the resulting plastic deformation and ductile fracture of the 776 layer composite was responsible for the enhanced FCP resistance. The ductile fracture mechanism produced a measurable temperature rise at the crack tip that revealed the stop-start nature of crack propagation.
Additional Material:
14 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1990.070400504
Permalink
